Smart cards are well known in the industry as being cards having computer chips embedded therein which are connected to metallic contact pads on a major surface of the card. These smart cards are insertable into smart card readers which make electrical contact with the pads of the smart card through contacts mounted in the smart card reader housing.
There are currently two types of smart card reader connectors available, sliding type and landing type. One example of the sliding type reader is disclosed in U.S. Pat. No. 5,334,827 by Bleier et al. Bleier et al. show a sliding type reader in which a smart card is inserted into the reader and is slid over the contacts until they are aligned with the pads of the smart card. The contacts are spring loaded against the smart card while the smart card is slid into the read position. A full normal force is exerted against the smart card during the entire mating and unmating cycle to affect a wiping action from the front edge of the card along the major plastic surface and finally on to the contact pads of the smart card.
A problem exists with the sliding type card readers as disclosed by Bleier et al. in that excess wear occurs on the reader contacts due to a long wiping path at a high normal force during the mating and unmating cycle. Also, as a result, debris is picked up by the reader contacts as they slide along the card surface. This debris is then deposited onto the card mating pads making it more difficult to achieve a reliable electrical connection. Another problem exists with such sliding type connectors in that the wiping path along the plastic surface of the card will mar any art work which appears on the surface creating undesirable streaks where the wiping action has occurred.
An example of the landing type smart card readers is disclosed in U.S. Pat. No. 4,976,630 by Schuder et al. Schuder et al. teach a smart card reading apparatus including a stationary frame and a contact element support mounted within an opening in the frame for reciprocal movement between a read position and an initial position. Movement of the contact element support into a read position is initiated by pushing the smart card into the reader. Return of the support to the initial position is accomplished by a spring which biases the support to the initial position upon removal of the smart card from the reader. Such a design is complex in that it requires the contact support to both translate in the mating direction and move transverse to the mating direction in order to land on the contact pads of the smart card.
Another example of a landing type smart card reader is disclosed in EP Patent No. 0 468 828 which teaches a smart card reader having a control lever. The control lever is pivotally attached to a support frame and controls the movement of the contacts so that they engage pads of the card when it is in the read position and disengage the card as it is withdrawn and in the idle position. A pair of helical springs serve to bias the control lever and contacts into the idle position whereby the contacts will not engage the card. The card, upon insertion, engages a cam surface of the control lever to pivot the lever and contacts toward the card pads to establish an electrical connection therebetween.
A problem exists with both of these landing type smart card readers in that they involve complex actuating mechanisms. Both designs require separate spring members to urge the contacts and/or the control lever. It is desirable to reduce the number of parts necessary in order to accomplish a simplified landing type smart card reader.